The midfielder's deal expired at the end of last season, but Blues boss Roy Keane has decided to offer the player a year's extension.

Keane watched Trotter in action when the 20-year-old was out on loan at Scunthorpe during their successful promotion campaign, and has acted to sign the player before the Iron themselves moved to make the loan deal permanent.

"I spoke to the manager and he said he wanted me to stay here, which was obviously a big boost for me," he told the club's official website.

"I'll admit I was a bit surprised. At the end of last season I thought I would be moving on, but with a new manager it's a fresh start.

"The manager has said I'll get the chance to show what I can do and that's probably the major factor in me staying."